2133 Alpha-tocopherol inhibits proliferation of tenon fibroblasts in vitro

HYAIJJRONIC Acn, CAN ENEANCE ‘IXE -0 LlFElMTION OF FJBROBLASTSINVITRO JOUSSEN AM, KRUSE FE, ROHRSCHNEIDER K, VijLCKER HE Q-J. of00 a Hyalumnic acid (HA) is a major component of viscoelastic substances which are widely used for intraocular surgery. HA is also naturally occurring in various parts of the eye and can be synthesized e.g. by stromal keratinocytes. Results from organ culture experiments indicate that HA has a mitogenic effect on the wrneal epithelium (Inoue, IOVS 1993;34:2313). We investigated the effect of HA on the proliferation of fibroblasta. MethQda 3T3 cells and explants fmm human conjunctiva or tenon were grown in RPM1 or DMEM with 10% calf serum (FBS) and antibiotics. Precontluent cells were grown at the low seeding density of 1.4 x 104 cells&O mm dish in medium with and without 1% FBS. HA was added to the medium in concentrations between 10 &ml and 1000 pg/ml. The number of cells and BrdU labeling was determined on day 3 and 6. &&& Control cultures without FBS and HA showed a very slow increase of the total cell number. Addition of HA to these “quiescent” cultures led to a dose-dependent, statistically significant increase of the cell number (p<O.OOl). In the presence of FBS morphology changed to a wider cytoplasm and cells formed small colonies. Addition of HA resulted in an dosedependent increase of proliferation (p<O.OOl). Conelusion Our results indicate that HA can be a mitogen for quiescent and actively dividing cells of fibroblastic origin in vitro. Although some caution has to be exercised when interpreting of data from culture experiments in respect to a clinical situation HA might also enhance proliferation in viva. To pay attention to this possibility, HA containing visco-elastic substances should be carefully removed when used for ocular filtration surgery.